Hill and mountain tractor four-wheel steering system and steering control method

The invention discloses a hill and mountain tractor four-wheel steering system and a steering control method. The hill and mountain tractor four-wheel steering system is composed of a four-wheel steering mechanism and a four-wheel steering hydraulic system. In a front-wheel steering mechanism body, the ends of piston rods of a front steering oil cylinder, front steering ball heads and one ends of front connecting rods are fixedly connected in sequence, and the other ends of the front connecting rods are hinged to front steering pulling rod ball heads which are connected with front steering knuckle arms. Cylinder bodies of front leveling oil cylinders are sleeved with the front steering knuckle arms and connected with a front drive axle. The other ends of the front steering knuckle arms are connected with front steering stand columns. The lower ends of the front steering stand columns are fixed to front steering knuckles which are connected with front wheels through front planetary wheel edges. The four-wheel